Network Effects and Cost of Railroad Crosstie

Network Effects and Cost of Railroad Crosstie
Maintenance and Replacement
Alexander Lovett, Tyler Dick, Conrad Ruppert
4 June 2014
Objectives
•
Develop a methodology for comparing the economics of
using timber or concrete crossties
•
Look at higher level and long term costs to get a complete
picture of the potential costs and benefits of each
crosstie type
Maintenance Planning - 2
Maintenance costs and benefits
•
Costs
o Consist of:
•
Benefits
o Consist of:
• Direct costs to performing
the maintenance
• Reduction in
derailment risk
• Indirect costs to delayed
trains
• Reduction in likelihood of
slow orders
o Depend on:
• Labor
• Equipment
• Decreased track
degradation rate
o Depend on:
• Materials
• Maintenance efficiency
• Train delay
• Track degradation rates
• Network effects
• Derailment costs
• Maintenance frequency
• Track class
Maintenance Planning - 3
Maintenance frequency
•
•
Number of good
ties
•
•
•
Crosstie life distribution was based on Forest Service
Product Curve (FSPC)1 with approximately 30-year tie life2
Model identified years when more than 800 ties needed to
be replaced based on the number of remaining ties from
each previous tie replacement for 20-inch tie spacing
Approximately 800-900 ties replaced every 9-10 years
Assume 850 ties are replaced every 9 years
For concrete ties, assume out-of-face replacement
every 45 years
3500
3000
2500
2000
0
Maintenance Planning - 4
50
100
Year
150
Estimated direct costs
Timber tie track renewal
$95 Cost per tie installed2
850 Ties replaced per mile
$80,750 Cost per mile per cycle
Concrete tie track renewal
$200 Cost per tie installed2
2,640 Ties replaced per mile*
$528,000 Cost per mile per cycle
Maintenance Planning - 5
*Assuming 24” tie spacing
Hourly delay cost components
•
Crew ($79.81)3
•
o
o
o
o
o
o
o Crew members per train
o Wage rate
•
Cars ($62.16)3
o Car types
o Cars per train
o Contractual car hire rate
•
Lading ($623.65)3
o
o
o
o
•
Revenue per train
Cycle time
Return ratio
Car availability
Fuel ($0, $59, or $518)4,5
•
Locomotives per train
Fuel cost
Fuel efficiency
Type of disruption
Length of disruption
Length of reroute
Total
Condition
Cost ($/train-hour)
Stopped
$839
Idle
$898
Running
$1,357
Locomotives ($73.81)3
o Locomotives per train
o Value of locomotive
Maintenance Planning - 6
Costs are per train-hour and based on the
nation-wide average for train composition
and using a 4300 HP mainline locomotive
Network effects
•
Delay will propagate through the network as trains are
rerouted resulting in increased congestion
•
Some delayed trains will result in connecting trains being
delayed or specific cuts of cars missing their connection
•
Delayed trains may result in crews running out of hours
before the planned crew change location
•
Delay cost can be found on a per-train basis, then applied
to all trains affected by the service disruption
o Disruption can be modeled using a rail traffic simulator
o Additional train-hours of delay and fuel use can be
determined
o Can use delay-volume curves
Maintenance Planning - 7
Maintenance situations
•
Infrastructure type
o Single track
o Multiple track
•
Network location
o Alternate routes available
o No possibility for rerouting
•
Types of disruptions
o Planned
o Unplanned
• Service failure
• Slow orders
Maintenance Planning - 8
Example Network
Single track with a portion of
double track and alternate route
Double track with
no route alternatives
Single track with
alternate route
Double track with
alternate route
Single track with
no route alternatives
Maintenance Planning - 9
Maintenance benefits
•
Benefits are primarily defined as the reduction in risk
o Risk = probability x consequence
•
Probability of a derailment is determined by the rate of
derailments of a certain type
•
The consequence is based on historical costs
•
Indirect benefits may result from a reduction in
maintenance associated with improved track condition
o These benefits can be considered when determining the life
cycle costs of a particular maintenance strategy
Maintenance Planning - 10
Derailment risk
Concrete
Timber
Traffic density (MGT)
76.2*
30.3*
Assumed miles of track
3,1656†
27,8066†
Percent of accidents
17%*
83%*
Accident rate per billion
gross ton-miles
0.152
0.208
Average accident cost
$354,4517
$354,4517
Accident cost per billion
gross ton-miles
$54,014
$73,727
Maintenance Planning - 11
•
Delay costs will vary
based on the operating
conditions
*based on data from a Class I
railroad
†assuming 6.5%8 of all crossties
are concrete
Slow order rates
•
•
•
•
FRA Track safety standards require a minimum number of
ties per 39 feet9
Slow order probability for an average 39-foot track section
was determined using the FSPC1
Number of slow orders over the entire line was
approximated using the 39-foot slow order probability as an
average for each line
This number was calculated for each year between tie
renewals and adjusted to assume that the ties replaced in
the previous year will not result in a slow order the next year
Maintenance Planning - 12
Slow order risk
•
The slow order rate per 39 feet is applied to the entire line
to determine a slow order rate per year for each route
•
The direct cost is calculated using the cost to install a tie
•
Delay costs are determined by multiplying the number of
trains affected, the additional time required to traverse the
slow order, and the delay cost
•
Assumptions
o
o
o
o
2 ties are replaced per slow order
Slow order is in place for 5 hours
Slow orders are imposed on tenth of a mile sections
Spot tie replacements don’t disrupt traffic
Maintenance Planning - 13
Other track maintenance
•
•
•
Concrete ties are reported to hold line and surface better,
but no published research was found to support this
Previous AAR research found that tie quality was not
found to significantly impact rail maintenance10
Higher bad tie counts were found to impact the cost
effectiveness of track surfacing10
Timber
Concrete
Surfacing cycle (years)
1
4
Surfacing cost per mile
$18,03111*
$6,34111*
* Adjusted to 2012 dollars
Maintenance Planning - 14
Case study
•
•
•
•
•
B: 20 TPD
49 MGT
B: 20 TPD
49 MGT
A:15 TPD
37 MGT
C: 45 TPD
110 MGT
D: 50 TPD
123 MGT
•
•
•
•
Maintenance Planning - 15
Class 4 track
Moderate climate
Range of curves
240 Mile legs
10 mile siding/
crossover spacing
2 mile sidings
6.5 hour work windows
15 minute start-up and
break-down time
6,723 tons per train6
NPV cost (millions of $)
NPV – Renewal costs
$300
Renewal - Direct cost
$250
Renewal - Delay cost
$200
Renewal - Network
costs
$150
$100
$50
$0
Tim
Con
A
Tim
Con
Tim
B
C
Route
•
•
Analysis was performed over 45 years
11% interest rate
Maintenance Planning - 16
Con
Tim
Con
D
NPV cost (millions of $)
NPV – Derailment costs
$100
$90
$80
$70
$60
$50
$40
$30
$20
$10
$0
Derailment - Direct costs
Derailment - Delay costs
Derailment - Network costs
Tim
Con
A
Tim
Con
Tim
B
Con
C
Route
•
•
•
Assuming 24 hour track outage after a derailment
Analysis was performed over 45 years
11% interest rate
Maintenance Planning - 17
Tim
Con
D
NPV – Slow order cost
NPV cost (millions of $)
$0.300
Slow order - Direct costs
$0.250
Slow order - Delay costs
$0.200
$0.150
$0.100
$0.050
$0.000
Tim
Con
A
Tim
Con
Tim
B
Con
Tim
C
Route
•
•
Assume concrete ties do not degrade enough to be the
cause of a slow order
Replace an average of two ties per slow order
Maintenance Planning - 18
Con
D
NPV – Surfacing costs
NPV cost (millions of $)
$250
Surfacing - Direct cost
Surfacing - Delay costs
Surfacing - Network costs
$200
$150
$100
$50
$0
Tim
Con
A
Tim
Con
Tim
B
C
Route
•
•
Analysis was performed over 45 years
11% interest rate
Maintenance Planning - 19
Con
Tim
Con
D
NPV – Cost summary
NPV cost (millions of $)
$350
$300
$250
Renewal cost
Derailment risk
Slow order risk
Surfacing cost
$200
$150
$100
$50
$0
Tim
Con
A
Tim
Con
Tim
B
C
Route
•
•
Analysis was performed over 45 years
11% interest rate
Maintenance Planning - 20
Con
Tim
Con
D
NPV – Direct cost summary
NPV cost (millions of $)
$350
$300
$250
Renewal cost
Derailment risk
Slow order risk
Surfacing cost
$200
$150
$100
$50
$0
Tim
Con
A
Tim
Con
Tim
B
C
Route
•
•
Analysis was performed over 45 years
11% interest rate
Maintenance Planning - 21
Con
Tim
Con
D
Future work
•
•
•
Gather validation data
Perform sensitivity analysis on the factors affecting life
cycle costs to determine which need more detailed values
Identify conditions where concrete ties are cost justified
Maintenance Planning - 22
Questions or comments?
Alexander Lovett
Graduate Research Assistant
Rail Transportation and Engineering Center (RailTEC)
University of Illinois at Urbana-Champaign
E-mail: [email protected]
This project is supported by the National University Rail Center (NURail), a
USDOT-RITA Tier 1 University Transportation Center, and the FHWA
Dwight David Eisenhower Transportation Fellowship Program.
Maintenance Planning - 23
References
1. MacLean, J.D. 1957. Percentage Renewals and Average Life of Railway
Ties No. 886, Forest Service Forest Products Laboratory. Madison, WI.
2. Railway Tie Association. 2008. RTA Tie Report #2.
3. Lovett, A. H. 2014. Direct Costs of Congestion and Train Delay. Presented at
Transportation Research Board Annual Meeting, Washington, D.C., January
2014.
4. Environmental Protection Agency. 1998. Locomotive Emission Standards
EPA-420-R-98-101. Environmental Protection Agency, Washington, D.C.
5. Frey, H.C. & Graver, B.M., 2012. Measurement and Evaluation of Fuels and
Technologies for Passenger Rail Service in North Carolina, North Carolina
Department of Transportation, Raleigh, NC.
6. AAR (Association of American Railroads). 2012. Analysis of Class I
Railroads. Association of American Railroads, Washington, D.C.
7. Federal Railroad Administration. 2013. Download Accident Data. Available
from:
<http://safetydata.fra.dot.gov/OfficeofSafety/publicsite/on_the_fly_download.
aspx>. [11 April 2014].
8. Uzarski, D.R. 2012. Learning Module 5 – Ties, lecture notes distributed in
CEE 409 at the University of Illinois at Urbana-Champaign, Fall 2012.
Maintenance Planning - 24
References
9. Federal Railroad Administration. 2014. Track and Rail and Infrastructure
Integrity Compliance Manual. Available from: <
http://www.fra.dot.gov/eLib/details/L04404>. [16 May 2014].
10. Elkaim, D. N., D. R. Burns, G. R. Cataldi. 1983. Effect of Tie Conditions on
the Costs of Performing Track Maintenance Operations WP-105. Association
of American Railroads, Chicago, IL.
11. Burns, D.R. 1987. M/W Cost Components: Part 1 – Surfacing. Railway Track
& Structures, pp. 34-39.
12. Sogin, S., C.T. Dick, Y-C. Lai and C.P.L. Barkan. 2013. Analyzing the
Incremental Transition from Single to Double Track Railway Lines. In:
Proceedings of the International Association of Railway Operations Research
(IAROR) 5th International Seminar on Railway Operations Modelling and
Analysis, Copenhagen, Denmark, May 2013.
Maintenance Planning - 25
Sogin delay calculations12
•
D=(S1-S2× x)ekV
o
o
o
o
o
o
D = Train delay (minutes/train)
S1 = Single track delay constant (19.5206)
S2 = Delay mitigation constant (19.149)
x = Double track percentage
k = Congestion factor (0.0471)
V = Traffic volume (trains/day)
Maintenance Planning - 26
Hypothesized relative costs
•
•
•
•
Costs may vary based on the conditions where the
maintenance is to be performed
Unplanned disruptions will always result in higher costs
including materials
Infrastructure can range from single track to having two or
more tracks
Network location can range from no alternate routes to
alternative routes of various levels of convenience to a
parallel route
Cost
Material
Equipment
Labor
Train delay
Network effects
Maintenance Planning - 27
Infrastructure
Single  Multiple
Constant
Increasing
Increasing
Decreasing
Decreasing
Network
No alt  Parallel
Constant
Decreasing
Decreasing
Decreasing
Increasing